title: Distal clearance margin of 1 cm or less: a safe distance in lower rectum cancer surgery.
abstract: OBJECTIVE
  The purpose of this study was to investigate the prognostic role of distal clearance margin (DCM) in lower rectum cancer surgery.
  
  
  METHODS
  Two-hundred-three cancer patients underwent total rectal resection, possibly followed by adjuvant chemoradiotherapy. DCM was classified as positive or negative (<1, > or =1 cm) and investigated with multivariable proportional hazard models.
  
  
  RESULTS
  A total of 52 deaths, 19 local relapses, 40 distant metastases, and three second primaries were observed as first events. Five-year survival with positive, negative <1, or negative > or =1 cm DCM was 51%, 81%, and 69%, respectively (p = 0.018). The difference was significant between positive and negative DCM (p = 0.031), not between negative <1 and > or =1 cm (p = 0.106). Local and distant 5-year incidences according to DCM were 30%, 8%, and 8% (p = 0.006) and 38%, 26%, and 19% (p = 0.857), respectively.
  
  
  CONCLUSIONS
  DCM, but not tumor size, is a prognostic factor after sphincter-saving surgery, which is safe whenever a negative margin is achieved.
authors.affiliation: Division of Colorectal Surgery, Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy.
authors.forename: Ermanno
authors.initials: E
authors.lastname: Leo
authors.forename: Filiberto
authors.initials: F
authors.lastname: Belli
authors.forename: Rosalba
authors.initials: R
authors.lastname: Miceli
authors.forename: Luigi
authors.initials: L
authors.lastname: Mariani
authors.forename: GianFrancesco
authors.initials: G
authors.lastname: Gallino
authors.forename: Luigi
authors.initials: L
authors.lastname: Battaglia
authors.forename: Alberto
authors.initials: A
authors.lastname: Vannelli
authors.forename: Salvatore
authors.initials: S
authors.lastname: Andreola
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D016016:Proportional Hazards Models; D012004:Rectal Neoplasms / Q000453:epidemiology / Q000601:surgery*; D012008:Recurrence; D016019:Survival Analysis